1. Field of the Invention
The present invention relates to a surgical device for applying fasteners to body tissues in order to suture and/or ligete the body tissues together.
2. Description of the Related Art
There is a case that the gallbladder needs to be extracted in order to prevent recurrence of gallstones. To extract the gallbladder, the cystic duct must be cut. Since the gallbladder arteries and veins extend through the cystic duct, the cystic duct must be sutured and/or ligated at a portion at the same time it is cut at that portion.
A tissue-fastening device is used to suture and/or ligate and a portion of the cystic duct in removing gallstones. The device is inserted into the body cavity through an incision made in the abdominal wall of the patient. The device is manipulated to apply staples, for example, to that portion of the cystic duct. A device of this type is disclosed in, for example, U.S. Pat. No. 5,084,057 and Jpn. Pat. Appln. KOKAI Publication No. 3-12126.
The device disclosed in U.S. Pat. No. 5,084,057 is designed to apply clips to tissues located in a body, to thereby fasten the tissues together. The device disclosed in Jpn. Pat. Appln. KOKAI Publication No. 3-12126 is of the type which is transcutaneously inserted into a body cavity to suture and ligate the tissues in the cavity. This device comprises an operation section; an insertion section connected to the operation section; a stapler attached to the distal end of the insertion section, including an anvil and a cartridge holding staples, capable of opening and closing; a firing lever for ejecting the staples from the cartridge; and a stapler-actuating lever for opening and closing the stapler.
While the tissue-fastening device is being used to staple and fasten the body tissues, the operation section, as well as the the insertion section, is contaminated with blood and other body fluids. The tissue-fastening device must therefore be washed and sterilized before it is used again. The device may be sterilized by various methods, such as gas sterilization, liquid-medicine immersion, or high-pressure, high-temperature sterilization in an autoclave. The autoclave sterilization is regarded as the best for environmental sanitation, since it achieves sterilizing with high efficiency and it does not use toxic gases or toxic liquid medicine.
The operation section of the conventional tissue-fastening device is not made liquid-tight. Water an liquid medicine may enter the device, damaging the internal components of the device. An electrically driven device has been developed, in which the fastening mechanism is driven by an electric motor provided in the operation section. The motor is driven by the power supplied from the dry cell or the battery contained in the device. When the device is sterilized in an autoclave, at a high temperature and a high pressure, the electrolytic solution will leak from the dry cell or battery. Furthermore, as well known, a dry cell and a battery are easily damaged by water or liquid medicine. Therefore, only gas sterilization may be applied to a tissue-fastening device containing a dry cell or a battery.
Certainly, the device containing a dry cell or a battery may have means for protecting the cell or battery from high temperatures and high pressures, so that the device may be sterilized in an autoclave. However, the use of such protective means will inevitably render the device complex, large and expensive.
Even if provided with such protective means, a device containing a dry cell or a battery causes a problem. Once used up, the cell or battery must be removed from the device, and a new one must be loaded into the device. If the cell or battery has not been sterilized, a person who removes it inevitably has his or her hands contaminated with dirt on the cell or battery.
The dry cell or the battery may be removed from the tissue-fastening device before the device is subjected to autoclave sterilization, and may be loaded back into the device after the device has been sterilized in the autoclave. However, it would be very cumbersome and time-consuming to open the cover of the cell or battery case and remove the cell or battery from the case. It would equally troublesome to load the cell or battery back into the case and close the cover of the case.